Package for holding pressurized fluent materials

ABSTRACT

A composite package for holding pressurized fluent materials such as carbonated beverages, beer, aerosols and the like, which includes a thermoplastic container having a hemispherically shaped bottom section with a projection extending outwardly therefrom and a support for holding the container in an upright position having an aperture formed in its end wall through which the projection extends, such that the end wall mechanically engages the projection after insertion so as to attach the support to the container.

United States Patent Doughty PACKAGE F OR HOLDING PRESSURIZED FLUENTMATERIALS Robert L. Doughty, West Hartford, Conn.

[75] Inventor:

Mansanto Company, St. Louis, Mo.

Dec. 28, 1970 Assignee:

Filed:

Appl. No.:

[52] U.S.Cl ..215/1C,99/171 B,2l5/l2R, 220/69 Int. Cl. ..B65d 23/00Field of Search .215/l C, l R, 12 R, 215/13 R, DIG. 6; 220/67, 68, 69;222/183, 184; 264/248, 249; 156/69, 293, 294; 79/171 [56] ReferencesCited UN lTED STATES PATENTS Heaton 215/12 R Schlablh et al. ..264/249Conner", ..215/13 R 3,419,297 12/ 1968 Diepenhorst et a1. ..264/2492,837,245 6/1958 Grebowiec ..2l5/l C FOREIGN PATENTS OR APPLICATIONS1,175,048 12/1969 Great Britain ..2l5/1 c Primary Examiner-Samuel B.Rothberg Assistant Examiner-Stephen Marcus Att0rney.lames C. bogomasini,Michael J. Murphy and Neal E. Willis 57] ABSTRACT 6 Clains, 3 DrawingFigures PATENTEDAPR1 11w 3; 727, 7 82 FIG.I

INVENTOR. ROBERT L. DOUGHTY ATTORNEY PACKAGE FOR HOLDING PRESSURIZEDFLUENT MATERIALS BACKGROUND OF THE INVENTION Such containers aredesirable because, generally speaking, they are relatively breakresistant, light in weight and readily destroyed after use. However, thematerials from which such containers are made are rather special in thesense of having to possess a large number of characteristics necessaryto accommodate these rather difficult to package contents. Accordingly,such special materials are costly to synthesize and therefore the amountused in each container should be the minimum necessary to allow thecontainer to function satisfactorily, if a profit is to be realized inthis phase of the highly competitive plastic packaging industry.

To contain the pressure of the contents, one approach used in the pastwas to make the container wall thicker but, as mentioned, this isuneconomical. Another approach is to design the container in such amanner as to minimize areas of high stress concentration. As isgenerally known, the area of highest stress concentration in anelongated container for holding pressurized materials is in the bottomsection along the general area of the confluence of the sidewall and thebase. As is also generally known, a base section in the form of ahemisphere takes maximum advantage of the strength of the thermoplasticfrom which the container is constructed since the surface area of such ashape per unit volume is smaller than that of any other base design.Such a hemispherical configuration for a container is disclosed in U.S.Pat. No. 3,480,168. Unfortunately, such a container configuration isincapable of supporting itself in an upright position on a horizontalsurface and requires some auxiliary means of support such as theintegrally formed feet illustrated in the referenced patent. Such feet,however, though providing some support when accurately shaped, wouldappear to require rather radical departures from conventional techniquesto form. In addition, they support the container at only a few pointsaround its periphery. In copending application Ser. Nos. 75,095 and75,096, each filed on Sept. 24, 1970, and assigned to the assignee ofthe present invention, the latter now abandoned, a similar container isshown wherein a separate support member is described which is snappedinto a mating depression in the container base or vice versa. Thoughsuch a configuration also would appear to function satisfactorily, thedeparture from a truly hemispherical shape necessary to accommodate thesupport detracts from the optimum configuration to the extent that suchsurface protrusions act as stress concentration points in the containerbase.

SUMMARY OF THE INVENTION Now, however, there has been discovered a newform of packagewhich overcomes the aforementioned deficiencies of theprior art.

Accordingly it is a principal object of this invention to provide animproved composite package for holding pressurized fluent materials suchas beer, carbonated beverages, aerosols and the like.

Another object of this invention is to provide a package of theaforementioned variety wherein the container is provided with a baseconfiguration which minimizes areas of high stress concentration.

A further object of this invention is to provide a package of theaforementioned variety wherein the container has an unmodifiedhemispherical base configuration and is capable of standing in anupright position on a flat surface by means of an auxiliary supportmember.

An additional object of this invention is to provide a package of theaforementioned variety which can be readily formed by conventionalmolding techniques without the need for any radical change in equipmentor in the molding process.

Other objects of this invention will in part be obvious and will in partappear hereinafter.

These and other objects are accomplished by providing a compositepackage for holding pressurized fluent materials comprising a one piecethermoplastic container having a substantially hemispherically shapedend section to minimize stresses generated thereon by said fluentmaterials, said end section having a projection thereon extending awayfrom said container, and means for supporting said container in anupright position which includes an end wall having an aperture thereinfor accepting said projection such that said end wall engages saidprojection after insertion so as to attach said supporting means to saidcontainer.

The projection preferably has a head portion on its leading end which isgreater in cross section than either the remainder of the projection orthat of the aperture. The head section is formed after the projection isinserted in the aperture by kissingthe protruding end with a hot surfacehaving a temperature above the softening point of the thermoplastic soas to melt and thereby enlarge the protruding end such that it isgreater in size than that of the aperture and thereby accordingly cannotbe removed therethrough.

BRIEF DESCRIPTION OF THE DRAWINGS In describing the overall invention,reference will be made to the accompanying drawing wherein:

FIG. 1 is a vertical sectional view of a preferred form of package ofthe present invention in a partially completed stage of assembly;

FIG. 2 is a schematic view of the bottom portion of the assembledpackage of FIG. I; and

FIG. 3 is a perspective view, of a portion of an alternative form ofcontainer usable as a part of the package of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to thedrawing, there is illustrated in FIG. 1, a composite package for holdingpressurized fluent materials generally indicated as 10. Package 10comprises a cylindrical thermoplastic container 12 preferably formed byconventional molding techniques such as by expansion of a tubularparison within closed sections of a partible blow mold. Container 12 isillustrated in FIG. 1 in the shape of a narrow necked bottle wherein thesize of the opening at the upper end of the side wall is between 20 to40 percent of the diameter of the body. Alternatively, however,container 12 may be in the form of a wide mouth can wherein the diameterof the opening through which the contents is dispensed is basically thatof the remainder of the sidewall, as illustrated at 14 in FIG. 3. Itshould be understood, however, that the size of the container outlet mayalso be intermediate that shown in FIGS. 1 and 3, as desired. Container12 is of one piece construction and is formed of a thermoplastic havingsufficient strength to withstand pressures, for example of between 20 to200 psi at wall thicknesses of from to 50 mils. Such thermoplastics areknown and include polymers of vinyl chloride and those wherein a majorconstituent therein has been formed from a nitrile group containingmonomer. Container 12 has a substantially hemispherically shaped bottomsection 14 which, because of its configuration, minimizes stressesgenerated thereon as a result of the pressure of the contents. Bottomsection 14 has a nub 16 extending outwardly from its otherwisecontinuous outer surface on the axis of cylindrical container 12. Thoughnub lid is of a relatively small size, for example between onethirty-second to one-fourth inch in length and one-sixteenth toone-fourth inch in diameter, satisfactory results may be obtained whennub 16 is in the form ofa portion of or all of the tail sectionconventionally formed in a blow molding operation when the leading endof a. thermoplastic parison is clamped between partible mold sections.When package 10 is in assembled condition, nub 16 has a head portion 18formed in a manner to be described in more detail hereafter which isgreater in cross section than the remainder of nub 16.

As a further part of package 110, there is provided a support 20 forholding container 12 in a vertical position on a horizontal surface.Support 20 includes a substantially vertical sidewall 22 and a concaveend wall 24 in intimate contact with substantially all of the outersurface 26 of hemispherical bottom portion 14. End wall 24 has anaperture 28 formed therein through which nub 16 projects. Aperture 28has a cross section which is less than that of nub headportion 18 suchthat head portion 18 is mechanically engaged with the section of the endwall of support .20 surrounding aperture 28 when the package is inassembled condition.

To assemble container 12 to support 20, container 12 is seated on endwall 24 such that nub l6 projects through aperture 28. A hot plate 29having a leading surface 30 at a temperature in excess of the softeningtemperature of the thermoplastic of the container is caused to contactnub 16. Accordingly, nub l6 melts partially and expands in a lateraldirection to form head section 18 thereon due to pressure exerted on itby hot plate 29 in the axial direction. Head section 18 after formationis in intimate contact with the outer surface of end wall 241 of support20 in the manner generally depicted in FIG. 3, such that nub i6 ismechanically interconnected with wall 24 and cannot be removed duringnormal use of the package. Thus, the manner in which container 12 isattached or secured to support 20 is of a mechanical nature, the surface30 of hot plate 29 as well as the time during which surface 30 is heldin contact with nub 16 not being sufficiently great as to cause anysubstantial melt bonding of nub head section 18 to end wall 24. To avoidsurface 30 sticking to nub 16, it may be necessary to coat it with arelease agent such as teflon. Though it is necessary for purposes of theinvention that the container be made of thermoplastic, it is possiblefor the support to be conveniently formed of any material. Thus, support20' may be of metal or any other break resistant material or for thatmatter of a thermoplastic which is relatively inexpensive in comparisonwith that necessary for the container, for example, low, intermediate orhigh density polyethylene. Because of the nature of the type ofinterconnection between the support and the container, it is possiblethat the thermoplastics of the two parts may be different sincecompatibility from the standpoint of bonding is not required.

The above description and particularly the drawings are set forth forpurposes of illustration only and are not to be taken in a limitedsense. Various modifica tions and alterations will be readily suggestedto persons skilled in the art. It is intended, therefore, that theforegoing be considered as exemplary only and that the scope of theinvention be ascertained from the following claims.

What is claimed is:

l. A composite package for holding pressurized fluent materialscomprising:

a. a one piece container formed of a thermoplastic having sufficientstrength to withstand the pressure of a carbonated beverage, saidcontainer having a I substantially hemispherically shaped end section tominimize stresses generated thereon by said fluent materials, saidcontainer having a thickness of between 10 to 50 mils, said end sectionhaving a projection thereon extending away from said container saidprojection having an integral head portion on its leading end; and

b. means for supporting said container in an upright position whichincludes an end wall having an aperture therein for accepting saidprojection, said head portion being mechanically engaged with a portionof said end wall to attach said supporting means to said container. v

2. The package of claim 1 wherein said container is a narrow neckedbottle. I

3. The package of claim 2 wherein said head portion is mechanicallyengaged with the inner surface of said end wall.

4. A composite package for holding pressurized fluent materialscomprising:

a. a container made of a thermoplastic capable of being blow molded,said container having a substantially hemispherically shaped stressminimizing bottom section with a nub extending outwardly therefrom onthe axis of said container, said nub having a head portion which isgreater in cross section than the remainder thereof;

b. a support for said container which includes a substantially verticalsidewall and a concave end wall in intimate contact with the outersurface of said hemispherical bottom section, said end wall having anaperture therein through which said nub pro: jects, said aperture havingacross section which is less than that of the head portion, said headportion of the nub being mechanically engaged with a portion of the endwall of said support surrounding said aperture.

5. The package of claim 4 wherein said support is formed of athermoplastic which is different from the thermoplastic from which saidcontainer is formed.

6. The package of claim 5 wherein said support is formed of low densitypolyethylene.

1. A composite package for holding pressurized fluent materialscomprising: a. a one piece container formed of a thermoplastic havingsufficient strength to withstand the pressure of a carbonated beverage,said container having a substantially hemispherically shaped end sectionto minimize stresses generated thereon by said fluent materials, saidcontainer having a thickness of between 10 to 50 mils, said end sectionhaving a projection thereon extending away from said container saidprojection having an integral head portion on its leading end; and b.means for supporting said container in an upright position whichincludes an end wall having an aperture therein for accepting saidprojection, said head portion being mechanically engaged with a portionof said end wall to attach said supporting means to said container. 2.The package of claim 1 wherein said container is a narrow necked bottle.3. The package of claim 2 wherein said head portion is mechanicallyengaged with the inner surface of said end wall.
 4. A composite packagefor holding pressurized fluent materials comprising: a. a container madeof a thermoplastic capable of being blow molded, said container having asubstantially hemispherically shaped stress minimizing bottom sectionwith a nub extending outwardly therefrom on the axis of said container,said nub having a head portion which is greater in cross section thanthe remainder thereof; b. a support for said container which includes asubstantially vertical sidewall and a concave end wall in intimatecontact with the outer surface of said hemispherical bottom section,said end wall having an aperture therein through which said nubprojects, said aperture having a cross section which is less than thatof the head portion, said head portion of the nub being mechanicallyengaged with a portion of the end wall of said support surrounding saidaperture.
 5. The package of claim 4 wherein said support is formed of athermoplastic which is different from the thermoplastic from which saidcontainer is formed.
 6. The package of claim 5 wherein said support isformed of low density polyethylene.